Advertisements
Advertisements
प्रश्न
A body of mass 5 kg falls from a height of 10 m to 4 m. Calculate:
The total energy possessed by the body at any instant? (Take g = 10 ms-2).
Advertisements
उत्तर
The total energy possessed by the body at
any instant remains constant for free-fall
It is equal to the sum of P.E. and K.E
∴ At height 10 m , i.e. at top most point K.E = 0
∴ Total energy = P.E. + K.E.
Total energy = 500 + 0 = 500 J
संबंधित प्रश्न
A boy of mass m climbs up a staircase of vertical height h.
(a) What is the work done by the boy against the force of gravity?
(b) What would have been the work done if he uses a lift in climbing the same vertical height?
A body of mass m is moving with a velocity v. Write the expression for its kinetic energy.
Name the energy changes for each of the following cases:
dynamo
Calculate the decrease in the kinetic energy of a moving body if its velocity reduces to half of the initial velocity.
What kind of energy is possessed in a situation when?
A stone, in a stretched catapult.
State two advantages and disadvantages of using nuclear energy for producing electricity.
State the energy changes which take place when:
A body released from rest from the top of a building.
State the energy changes which take place when:
A magnesium ribbon burns in air.
State the energy changes which take place when:
A battery lighting up a bulb.
A body is thrown vertically upwards. Its velocity keeps on decreasing. What happens to its kinetic energy as its velocity becomes zero?
